Flush Cooling System

PY4157-UN-28AUG04

PY4158-UN-28AUG04

PY1234-UN-11JUN02

PY4159-UN-28AUG04

A - Radiator Cap

B - Drain Plug

C - Coolant Drain Plug

D - Thermostat Cover

For efficient operation, drain old coolant, flush the entire system, and fill with clean antifreeze solution at least once every two years.

1. CAUTION: DO NOT remove radiator cap or drain coolant until coolant is cold. Always loosen radiator cap slowly to relieve any excess pressure.

   Drain coolant - Remove radiator cap (A). Open drain plug (B) on radiator and attach a drain hose. Route hose to container and drain coolant from radiator. Drain coolant from engine block by removing plug (C).

2. IMPORTANT: Thermostat must be removed to ensure a thorough flush.

   Remove thermostat cover (D), remove thermostat and install cover (without thermostat). Tighten cap screws to specification.

   Item	Measurement	Specification
   Thermostat Cover Cap Screws	Torque	47 N˙m (35 lb-ft)

3. Flush system with water - Close all drain valves/plugs and fill system with clean water. Run engine about 10 minutes to stir up possible rust or sediment. Stop engine and drain water from system before rust and sediment settle.

4. Flush system with radiator cleaner - Close all drain valve/plugs and fill the cooling system with a good commercial radiator cleaner and water. Follow instructions provided with cleaner. Stop engine and immediately drain system.

5. Flush system with water - Close all drain valves/plugs and fill with clean water to flush the system. Run the engine about 10 minutes, then drain out flushing water.

6. Remove thermostat cover and clean off the gasket material. Apply gasket sealant to new gasket and install thermostat and cover. Tighten cap screws to specification.

   Item	Measurement	Specification
   Thermostat Cover Cap Screws	Torque	47 N˙m (35 lb-ft)

7. Fill with fresh coolant - Close all drain valves/plugs and fill with a mixture of antifreeze, soft water, and coolant conditioner as specified in the Fuels, Lubricants, and Coolant section.

8. Check coolant level - Fill radiator to the top of the filler neck. Run the engine until operating temperature is reached. Let the engine cool (preferably overnight) and recheck the coolant level. Coolant level with a cold engine should be at the bottom of the filler neck. When filling the cooling system it may require several operating/cooling periods to stabilize the coolant level in the system. Add make-up coolant to the radiator as needed to bring the coolant level to the correct level.